This work focuses on the well-known common spatial pattern (CSP) and Riemannian covariance methods, and significantly extend these two feature extractors to multiscale temporal and spectral cases.
Accurate, fast, and reliable multiclass classification of electroencephalography (EEG) signals is a challenging task towards the development of motor imagery brain-computer interface (MI-BCI) systems. We propose enhancements to different feature extractors, along with a support vector machine (SVM) classifier, to simultaneously improve classification accuracy and execution time during training and testing. We focus on the well-known common spatial pattern (CSP) and Riemannian covariance methods, and significantly extend these two feature extractors to multiscale temporal and spectral cases. The multiscale CSP features achieve $\pmb{73.70\pm15.90\%} (\mathbf{mean}\pm$ standard deviation across 9 subjects) classification accuracy that surpasses the state-of-the-art method [1], $\pmb{70.6\pm 14.70\%}$, on the 4-class BCI competition IV-2a dataset. The Riemannian covariance features outperform the CSP by achieving $\pmb{74.27\pm15.5\%}$ accuracy and executing 9x faster in training and 4x faster in testing. Using more temporal windows for Riemannian features results in $\pmb{75.47\pm 12.8\%}$ accuracy with 1.6x faster testing than CSP.
Pasquale Davide Schiavone
2 papers
Tino Rellstab
1 papers
Lukas Cavigelli
1 papers